Symptoms of Colorectal Cancer

The earliest stages of colorectal cancer have no symptoms. Colorectal tumors can grow slowly over the course of several years, which may only cause subtle symptoms at later stages. If you experience any symptoms, do not assume it is due to cancer. Many symptoms can be caused by other, less serious conditions. However, it is still important to discuss them with your doctor. Early detection and treatment improve outcomes for both cancer and other health conditions.

Common Symptoms

Symptoms will vary depending on the location of the tumor or how long it has been growing. The 2 most common symptoms of colorectal cancer are:

Keep in mind that bowel habits and function are different for everyone. The changes you notice may be unique to you, but these are general changes to be aware of. If you detect changes that last at least 6 weeks, contact your doctor.

Bleeding

Tumors can cause bleeding, but sometimes it cannot be seen, especially if the tumor is in the first sections of the colon. If blood in the stool cannot be seen, it is called occult blood. There are specific tests that can detect occult blood in the stool.

Blood that is visible may appear as:

Red blood from the rectum during a bowel movement without other anal symptoms, such as itching, pain, or lumps

Stool is streaked with red blood

Stool is dark, tarry, or black

It should be noted that any rectal bleeding, with or without a bowel movement, should prompt a call to your doctor. Rectal bleeding can be caused by noncancerous conditions, such as hemorrhoids, which may require medical treatment.

Revision Information

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.